12
•
At high level 5 cm
2
for each kW of
rated heat input
•
At low level 10 cm
2
for each kW of
rated heat input
The high level ventilation opening should be
sited on an external wall and positioned as
high as is practical and always within the top
15% of the wall height
The low level natural ventilation opening
should be situated on an external wall and
be within 1000 mm of floor level for natural
gas and ideally at floor level for l.p.g gas
installations but in any event no higher than
250 mm.
The table that follows provides specific data
for each heater model as -
2.3.2.5 Mechanical Ventilation to a
Plant Room or Enclosure
In the event that the installer prefers to
mechanically ventilate the plant room or
enclosure rather than provide ventilation
openings then -
•
The plant room or enclosure needs to
be mechanically ventilated at the rate
of 4.14 m
3
/h of fresh air per kW or
rated heat input.
•
It is a requirement that the mechanical
ventilation shall be of the ’input’ type
with either natural or mechanical
extraction. Where mechanical
extraction is selected then the
extraction rate should be 5%-10% less
than the input rate.
•
Systems of mechanical extraction with
a natural inlet shall not be used
•
It is necessary to provide an automatic
means to safely inhibit heater(s)
operation should mechanical air
supply fail for any reason
The table that follows provides specific data
for each heater model as -
Minimum Free Area Of
Ventilation Opening
High Level
Low Level
cm
2
cm
2
30
160
320
50
267
533
72
394
788
95
527
1053
120
656
1312
145
787
1574
MODEL
MODEL
Mechanical Ventilation
Rate for Plant Room or
Enclosure
M
3/
h
30
133
50
221
72
327
95
436
120
543
145
652
Summary of Contents for HT2000
Page 51: ...51 Notes...